Solidus Biosciences, Inc. in partnership with the University of California, Berkeley, and Rensselaer Polytechnic Institute are proposing to address a critical need in drug safety technology through its proprietary "metabolic stability" chip (or Metabolizing Enzyme Stability Assay Chip, or MesaChip) for high-throughput analysis of drug candidate metabolism. The MesaChip is being developed to provide the pharmaceutical industry user with the ability to mimic the first-pass metabolism of the human liver. While in recent years there has been a dramatic increase in the number of new chemical entities (NCEs) and screenable drug targets, such increases in productivity have not translated into an increased number of new drug approvals, in part because of the high failure rate due to toxicity of the NCE or its metabolite(s). A critical component of drug safety evaluation is the metabolic stability of a drug candidate, which reflects the susceptibility of a drug candidate to be metabolized and the rate of such metabolism. Early stage metabolic stability analysis, however, is currently limited by the inherent low throughput of methods available that provide accurate quantitative measurement of drug candidate metabolism. As a result, accurate information required for early-stage high-quality decision making is lacking. The specific aims of this Phase I project are to: 1. Develop well-based fluorescence assays that enable determination of P450-catalyzed substrate oxidation rates from concurrent measurements of oxygen and NADPH consumption and of H2O2 formation. 2. Verify using LC-MS that the above rate measurements can be used to calculate accurate rates of P450-catalyzed oxidation reactions. 3. Adapt the well-plate assay techniques developed in Aim 1 to a high-throughput microarray format (MesaChip) based on the MetaChip platform that involves P450s incorporated into microspots (< 30 nL) on a functionalized glass slide. Once fully developed, the MesaChip will provide a robust and high-throughput technology platform capable of providing pharmaceutical researchers with the information needed to predict the in vivo metabolic stability of drug candidates, and thus help to decide which compounds are brought forward for lead optimization. This capability is also a critical precursor to the widespread adoption of personalized medicine, where differences among individuals in drug metabolism can be predicted, thereby providing information on the potential outcome of drug therapy at the individual patient level. The goals of this STTR project, therefore, fit the goals of the National Institutes of Health. The drug discovery process is an investment-intensive, high-risk endeavor that results in low yields of effective and safe drugs; a problem that is confounded by the significant lack of information that exists in predicting the metabolic fate of drug candidates, in general, and in predicting the reactivity of drug candidates in the human body. The proposed STTR project for the development of Solidus Bioscience's MesaChip technology has significant relevance to public health by providing pharmaceutical researchers with the information needed to predict the in vivo metabolic stability of drug candidates, and thus help to decide which compounds are brought forward for lead optimization and the ultimate development of better and safer drugs. [unreadable] [unreadable] [unreadable]